From: Theodore Ts'o Subject: Re: xfstest-bld generic/018 fails due to e4defrag issue Date: Wed, 9 Apr 2014 18:03:20 -0400 Message-ID: <20140409220320.GC15303@thunk.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "linux-ext4@vger.kernel.org List" To: jon ernst Return-path: Received: from imap.thunk.org ([74.207.234.97]:52242 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933705AbaDIWDY (ORCPT ); Wed, 9 Apr 2014 18:03:24 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: On Wed, Apr 09, 2014 at 01:37:04AM -0400, jon ernst wrote: > running latest xfstest-bld with latest ext4 kernel "dev" > branch(ad6599ab3a).I always get generic/018 failed. > Then I took closer look and found out this issue. That's a renamed tested; it was previously shared/218. It's a test which is known to fail for ext4, since its idea of how a defrag program should work is slightly different from how e4defrag works: shared/218 7s ... [20:48:32] [20:48:39] - output mismatch (see /results/results-4k/shared/218.out.bad) --- tests/shared/218.out 2014-04-01 18:46:39.000000000 +0000 +++ /results/results-4k/shared/218.out.bad 2014-04-03 20:48:39.795694518 +0000 @@ -10,7 +10,7 @@ After: 1 Write backwards sync, but contiguous - should defrag to 1 extent Before: 10 -After: 1 +After: 10 Write backwards sync leaving holes - defrag should do nothing Before: 16 ... (Run 'diff -u tests/shared/218.out /results/results-4k/shared/218.out.bad' to see the entire diff) What you are seeing is something very different, though. > Even though the file does exist. e4defrag complains about: > > (this output comes from kvm guest machine) > > e4defrag -v /vdf/testfile > Can't get super block info: Success > "/vdf/testfile" > > Is this a known issue or something I did wrong. Unfortunately, e4defrag has horrible error handling, so we can't see the error code properly, so we can't see why it's failing, but this is from an attempt to open the file system to get some low-level information. How is /etc/mtab set up on your test machine? It looks like it failed to find block device for the file system in question. - Ted